Display screen with a transitional graphical user interface



FIG. 1 is front view of a first image in a sequence of a display screen with a transitional graphical user interface; and,

FIG. 2 is a front view of a second image thereof.

The broken lines illustrate the display screen and form no part of the claimed design. The broken lines illustrate portions of the graphical user interface and form no part of the claimed design. The appearance of the transitional image sequentially transitions between the images shown in FIGS. 1-2 in forward or reverse order. The process or period in which one image transitions to another image forms no part of the claimed design. 

CLAIM The ornamental design for a display screen with a transitional graphical user interface, as shown and described. 